TKD pot and other mods

[Riggers]

Hi all,
As I have had my WD pre3 for 7 years I wanted to look at possible upgrades and have just installed a TKD 2CP-2500 volume pot, replacing the standard Alps pot. The Alps functioned well enough and was given the shunt mod a few years ago.

The pot wasn’t noisy but my main issue with the Alps was it’s feel, which felt overly light (cheap!?!) and not entirely smooth, if that makes sense. I have no idea if this was an anomaly as I did not have another with which to compare.

The TKD gives a subtle but noticeable improvement in clarity and has that beautiful syrupy smooth action to boot. The design is already a shunt type attenuator which simplifies wiring up. Whether it’s worth the cost is up to you but I feel it tops off an already great performer.

I also installed some ETI research speaker posts and input RCA jacks on my WD88VA. The original items were fine but these I feel put high quality finishing touches on an amp I am very proud to have built. ETI are an Aussie company (available at hifi collective in your part of the world). The binding posts in particular are a wider diameter than the original parts which required a little surgery on the back of the chassis to install. No solder tags on the internal connection for the binding posts (apparently avoids some capacitance!?) but easy enough to connect.

Best regards for 2021

Phil.

I’ll post a couple of pics when I get the chance.

[bob orbell]

Hi Phil, I amongst others don't like the shunt pot configuration, the changing impedance to the source is not good, I have tried it a few times and reverted back in under half an hour. If you really want to improve the Pre III, go fully regulated HT, Morgan Jones quotes, the best way to improve an amplifier is to use regulated HT, he isn't wrong, I now have two regulated PSU's one for the Pre and one for the phono, divine . Bob

[pre65]

Looking at the TDK data sheets they do not look like (to me) as a shunt pot is wired up in our FAQ section.

[bob orbell]

I think this has been mentioned before Philip, but don't remember the outcome. Bob

[A Stuart]

Originally Posted by pre65

Looking at the TDK data sheets .....

As I understood it - he did not have to set up the modification as he had done that bit some years earlier, so it was simply a case of dropping in pot for pot. I could be wrong, of course.

Alastair

[Riggers]

I have wired in the TKD pot in standard as per original build instructions, (ie no longer signal in connected to a series resistor and shunt configuration). I admit that the data sheet and description from TKD confuses me a little but I definitely prefer the sound now, even at the expense of lowered attenuation and less usable range of volume knob.
Phil.

[Riggers]

This is the blurb from Hifi Collective re TKD pot:

" Please note this is not your standard taper potentiometer but is a shunt attenuator/taper type to give you better performance than your standard taper potentiometer."

It didn't make sense to me to connect the TKD pot as per shunt mod diagram in Richards article in the tweaks page.

Phil.

[Riggers]

IMG_2605-1.JPG

IMG_2606-1.JPG

Here are the pics of the ETI connectors on the WD88VA. Note no solder connections on internal aspect of the speaker binding posts.

Phil.

[Chris]

That looks really nice Phill, I guess the amp kits have basic connectors as adding the extras in the kit build would push up prices substantially, adding later when the upgrade bug bites will bring extra refinement to the sound.

Screw termination has the advantage of making a good connection without the difficulty of using high soldering heat on heavy binding posts, the up on soldering the connection is that it tins the wire and prevents the copper from being exposed to air and can hold the multistrand wire together.

Chris..

[bob orbell]

Chris, why do you mention soldering ? the cable is fixed by the screw, I can see no solder and as for an improvement in sound is concerned, . Bob